Introduction: Ocean acidification (OA), resulting from the absorption of increasing atmospheric CO2 by the oceans, represents a major threat to marine organisms. Despite growing concern, the biochemical responses of Antarctic species to OA remain poorly understood.
Methods: This study investigated the impact of OA (pH 7.70 ± 0.09) on the fatty acid (FA) composition of the Antarctic snail Neobuccinum eatoni over a two-month experimental period (December 2015–March 2016). Fatty acid profiles were analyzed in multiple tissues to assess potential alterations induced by low-pH (LpH) conditions.
Results: Significant tissue-specific changes in FA composition were detected, particularly in the mantle and gill. Under LpH exposure, notable modifications occurred in long-chain polyunsaturated fatty acids (LC-PUFAs) such as 22:5n-3, 22:6n-3, and 24:5n-6. Elevated LC-PUFA levels in the mantle suggested a compensatory response to oxidative stress, while shifts in the n-3/n-6 ratios in the gill pointed to potential alterations in immune and anti-inflammatory functions.
Discussion: Indicators of homeoviscous adaptation (HVA), including PUFA/SFA ratios and mean chain length (MCL), revealed biochemical strategies used by N. eatoni to maintain membrane fluidity under acidified conditions. This study provides the first evidence of FA-based responses to elevated pCO₂ in an Antarctic gastropod, highlighting the potential of fatty acids as sensitive biomarkers of physiological adaptation to environmental stressors.
Servetto N., De Troch M., Alurralde R. G., Ferrero L., De Aranzamendi M. C., & Sahade R., 2025. Effects of ocean acidification on fatty acid composition in the Antarctic snail Neobuccinum eatoni. Frontiers in Marine Science 12: 1645755. doi: 10.3389/fmars.2025.1645755. Article.
